Continuous boiling-out still.



No. 853,986. PATENTED MAY 21, 1907. J. T. LUDLOW a; 1). MOSHER.

OONTINUOUS BOILING OUT STILL.

APPLICATION FILED APR. 18.

Gt: I MTNEss s. ENTORS QHQMTQQAL 4 4241-644 A UNITED STATES PALIENT OFFICE;

JAMES 'T. LUDLOW AND DAVID MOSHER, OF SAN FRANCISCO, CALIFORNIA.

com'muous aolLme-our STILL. v

Application filed April To (til whom it may concern.-

- process secured to the said Mosher by Let- Y-ters-Patent of the United States N 0. 30,835,

' granted June 9th, 1903.

As economy in o eration, and initial low cost of plant are of, t e utmost im ortance in' the profitable development and andling of low grade ore-bodies, the general purpose of our invention'is to secure these results by an i the boiling-out sti l, of a heat interchanger,

a paratus in which a continuous boilin out o themetal oxid, and the recoverggo the amm'oniav are possible; while, at t e same time, by the emplo ment, in connection with such as we shall describe, the heat units from the waste hot boiled-out solution are utilized,

thus efi'ecting importantv economy. In 'addition to the advantages flowing from these considerations the apparatus is of such a nature that by its continuous action,- the exensive construction of boiling-out stills of liuge dimensions such as heretofore pro osed is avoided, and we are able tohand e, in twenty-four hours, large volumes of solution from hundreds of tons of ore, in a still of small cubic capacity, the size of which is, in itself, an item 'in the saving of constructive expense. I 1

Our invention consists, in general terms, of

an apparatus the chief feature of which is a boilin out still, having'such connections that uring-the process of boiling out to libcrate the ammonia from the/solution and to precipitate the metal oxid; the metal 'oxid ammonia solution is supplied to the still and the waste hot boiled out solution is discharged from the still, in a continuous flow or operation.

. Our invention further consists of a boiling Y out still and an associated heatinterchanger relatively connected such manner that the Specification of Letters Patent.

18,1904. Serial No- 203,556.

, A is the boiler or still in which Patented May 21, 1907.

and absorber to be returned to the supply of metalsolvent for use over and over again,

Our invention also consists the novel ap aratus which we shall now describe by' re erence to the accompanying drawings in which the figure is a general view of our ap paratus.

oxid ammonia solution is hailed, the ammonia liberated and the boiled-out'metal -oxid precipitated. With this, still are made the valve controlled connections a, from the the metal steam pipe 0/, by which connections steam is let into the still for boilin the solution. In

the to of the still are the attic plates (L bea suitable casing the a connection 5 with t ischarging it into the chute a A 48 B is the heat inter'changer. It consists of upper head of which has e still, by which conmotion the hot-boiled 'out solution from the i still passes over to the heat interohanger. In the latter are tubes 6 through-which the hot-.bbiled-out solution passes to the base of the de'vice from which, by a pipe 6 it is conducted to the settlin tank controlledby the va ve b;

vFrom leaching tanks, barrels, etc.,- not sourceof supply of the inetalsolution from the ore,,extends a pi e b to the lower portion of the heat interc anger casing, whereby' said solution is passed into said .interchanger, and flowing upwardly around and in'c'ontact with its tubes 1) passes therefrom b the pipe 1) into the lower portion ofthe sti It w ll thus be seen that the heat interchange! comprises separate assagesin".proximity, the waste hot boile -out solution from the" still flowing through one passage and through the F, said pipe being herein shown, and which constitute the heat interehanger, and giving up itsheat to the incoming cold ammonia-metal oxid solution, which continually flows through the other passage of the interehanger, andsaid '5 solution when introduced, by the pipe 6, into the still, is'thus already heated to a large extent. I i

C is the condenser for the ammonia gas and water vapor from the still. This coni denser is connected with the still by the p pe c and it hasdraih i es 0, the continuation Q of which connects wit the absorbing drum (1 of the tank I), which holds the aqua-ammonia solution. The condenser is sup lied :5 with cold water from the tank E throng the" connection c. From the lower portion'of the condenser extends the water overflow pipes c leadingto the'tank G below. A pipe from the condenser carries off the non-con- 2o dens'ible vapors, while the top of the condenser is provided' with a water distributer 6. The absorbin druind discharges through holes d in its lower portion into the tank I), and from said tank the ipe d leads back again to the leaching-ts ks,- barrels,

etc. containing ore or tailings.

The water tank E has a pipe cflwhich supplies the absorber and a pipe e for a general supply for washing the ore.

ing oil' the precipitate, and valve-controlled pipes j" connected with a pi e f for draws mg oil' the clear liquid. In t ev storagetank G the liquid is allowed to cool.-

3 5 ll is a car under the settling tank to carry away the precipitate.

I is a pump pipe '5 to the tank E.

It will thus be seen that the ammonia gas 0 driven off in the still is condensed and returned to the stock solutions for use over and over again in dissolving the ammonia-soluble metals fr the ores. In the process of treating copper, nickel and zinc ores with 4,5 gold and silver values, as described in the patent referred to, the idea is first to transform the metals suchas copper, nickel or zinc, present in whatever form in the ore, into a condition soluble in ammonia solutions of varying strengths j leaching such ammonia,- co per, nickel or zinc solutions from the ore y known methods, andunder conditions which will, as much as possible, prevent loss of ammonia; then by boiling the ammonia solution of metal hydroxid, car-' bonate or sulfate the metal is precipitated as oxid at the boiling point of water, and-is thereby practically rendered anhydrous.

'lhe ammonia passes over as vapor to be reabsorbed by cold water or cold boiled out waste solution for use with slight loss, over and over again;

The apparatus i'ghich We have herein de- "scribed accomplishps the metal oxid precipi- 5 tation, and ammonia recovery in such an upward through the heat interfihanger and The settling tank I has a gate f for draw-' 2. In an apparatus o to supply water through the other to the still the ammonia metal oxid economical and continuous manner, with 1 large output for the small cubic capa'city and compactnessof thestill, as to make-it of great value in the treatment of ores bythe; ammonia and ammeniaecyanid processes. 0

Having thus described our invention, what we claim as new and desire to secure by Letters Patent, i's

1. In an apparatus of the class described, the combination with a continuous boiling 5 out still having a discharge for metal OX1(l preei itate, an outlet for ammonia gas, an mlet below for ammonia metal oxid solution, and an outlet above for the discharge of hot boiled'out solution, of a; heat interchanger comprising separate passages in proximity, separate connections with said passages to receive in onethe waste hot boiled out solution from the still, and to deliver from. the other to the still the ammonia metal oxid 8 solution to be treated, a discharge outlet for the boiled out solution, an-inlet for the ammonia metal oxid solution,-and means for continuously-supplying ammonia metal oxid solution to the heat interohan er, whereb 9o thei-boiled outsolution passes cm the st' 1 downward through the heat mterehange'rand is cooled, and the ammonia metal oxid' passes is heated beforeenterin the stil L f the classldesc'ribed, the combination. of a continuousboilingout still having a,discharge for metal oxid precipitate and an outlet for ammonia gas, a

heat interchanger havingfseparate passages I00 in proximity, and separate connections etween said passages and the still for receiv: ing in the one thewaste hot boiled out solution from the stillfand delivering'from the solution to be treated, a connection from the I source of said solution with the last named passage, and a discharge for the boiled out solution from the other passage, a condenser for the ammonia gas, an. absorber in connection therewith, a tank for receivin the boiled out solution from the heat mterchanger, and means for conveying said iio boiled out solution'froni said tank to'the condenser tobe used as a cooling medium therefor.

3-. In an apparatus of the class described, the combination of a continuous boiling out .still having a' discharge for metal oxid precipitate and an outlet for-ammonia gas, a heat interchanger having separate passages in proximity, and separate connections between said passages and the still for receiving in the one thewaste hot boiled out solution from the still, and delivering from the 5 other to the still the ammonia metal oxid i solution to be treated, a connection from the source of said solution with the last named passage, and a dlscharge for the .boiled out solution from the other passage, 9'. Lpnden'ser. -3

for the ammonia gas, an absorber in 0011360- tion therewith, a tank boiled out solution fl-mm the changer, means for col'weying said boiled out solution from said tank to the condenser for a cooling; medium, and means for conveying the boiled out solut'mn from the mm; to the absorber.

l 1x 1 witness whereof We have hereunto set for recewmg the l heat 111ter-.-

cup-hands.

JAMES T. LUDLOVV. DAVID MOSHER.

\ Witnesses:

WALTER F. VANE, D. B. RICHARDS. 

